I have not read all the responses, so I don't know if these were mentioned.
Most Christians find a careful search of the scriptures distasteful and let someone else tell them what someone else thinks they need to know. This is, of course, dangerous.
Dragon - is mentioned 28 times in the Bible
Behemoth - is described in Job 40:15-24
Leviathan - is described in Job 41; Psalm 104:25,26; Isa.:27:1
Carbon-dating is an inexact science, and millions of years are, actually, rather illogical.
http://www.clarifyingchristianity.com/dinos.shtml
Or, do a little research of your own.